package chai.ning.polym;

public class Circle extends Shape {
	
	private double radius ;

	public Circle() {
		super( "圆" );
	}
	
	public Circle(double radius) {
		super("圆");
		this.radius = radius;
	}

	@Override
	public void calculate() {
		this.area = Math.PI * Math.pow( this.radius , 2 );
	}

}
